Fluorescent illuminating device



Jan. 10, 1939. G. T. SCHMIDLING FLUORESCENT ILLUMINATING DEVICE Filed Oct. 6, 1934- s Sheets-Sheet 1 Z2 V V 1 v 'l I,

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I x 1 mTm n w ill I 9 Z? r All INVENT'OR' 4 5 a 4 fiZZfiB/iTJi/ii/Zldllilj ATTORNEY$ j Y WY Jan. 10, 1939. G. T. SCHMIDLING FLUORESCENT ILLUMINATING DEVICE Filed Oct. 6, 1934 3 Sheets-Sheet 5 M ATTORNEYS Patented .lan.10,'1939 v t 2,143,527

UNITED STATES PATENT OFFICE 2,143,527 FLUORESCENT ILLUMINATING DEVICE Gilbert T. Schmldling, Kew Gardens, N. Y., as-

signor to Eastern Electronics Research Inc., Brooklyn, N. Y., a corporation of New York Application October s, 1934, sci-ml No. 747,162 3 Claims. (01. 250-141) The present invention relates to a fluorescent salts are applied to glass and bombarded on the illuminating device, wherein the brilliant fluoside opposite to the side from which the effect rcscence is produced by cathode rays acting upon is viewed.

fluorescent materials enclosed in a glass cham- Another characteristic of the present invention 5 her which has been exhausted to a very high is that a relatively large surface is used as an 5 vacuum. emitter for the cathode rays and this surface is The surface upon which the luminescent mauniformly heated by a suitable electrical heater terials are mounted preferably is a cold metallic in such manner that the cathode emanations are anode which is located in the path of cathode u rm Over t s ar e surface area and d0 RM? rays preferably emanating from a hot cathode. p e t an a e o e heating 0011- Si ce t e 10 This luminescent anode may be composed of variy emanate m h ot a h de a d trave ous materials, but one material which gives partoward the cold luminescent anode, the Present ticularly satisfactory results is a plate of nickel. device Operates y use Of an alternating Current, Other metals may be used s ch as a i in view of the fact that luminescent materials,

copper, etc. The plate may have an oxidized rwhen once activated by electronic bombardment, l5 face, for exam le, a copper plate covered t remain active for a substantial interval without oxide of copper. greatly diminishing in brilliance. Consequently,

Intermediate the cathode and the anode is an the Ordinary alternating current astivetes the electronic lens constructed to spread the beam of luminescent materials at a rate so far above he w cathode rays into the form of a cone so that luminescent lag of the salts as to Prevent rm the entire area of the luminescent anode is withdetection Whatever of variation in luminosity in the ath of th spread cathode ray beam cause of the intermittent bombarding action prowhich reacts with the entire area of the luminesdused by the alternating current Wh ch is autoe nt, anod matically rectified by the hot cathode and the The anode may tak th form of a figure cold anode. While the potential applied to the shown eith i silhouette or by a painted com electronic lens is reversed for each alternating figuration on the anode plate, and various porcurrent Cycle, this P n i l ways bears the tim f th figure may be coated t himinescorrect relation to the cathode rays when these cent materials which will give off visual rays of rays are emanating from the hot Cathode and difi r t c l so t t when t device is travelling toward the cold luminescent anode, 30 ating, a brilliantly illuminated colored figure will and, therefore, the beam is always Properly be produced. Where this arrangement is used, This is becausethe rays are y emitted the device is particularly effective as an advertiswhen the cathode is negative relatively to the ing medium. The cathode ray being invisible, the anode- Preferably, the luminescent anode s entire illumination a t from the fluore angularly disposed relative to the axis of the c nt fi hi is muminated over the entire cathode tube and relative to the axis of the cone surface area where a luminescent material is of cathode rays- This renders the s en provided. In this way, extremely brilliant and Surface effective for bombardment and i n adbeautiful color effect may be produced. vantage in viewing t image pa icularly wher Where the device is used for illumination, the the device is used h show Windows for fl sluminescent anode is preferably arranged in the ihg Purposesform of a cone comprising a metallic anode Since the cathode emitter is of relatively large ber covered with a luminescent material that is area and is uhiiormiy heated, so as o rm bo b d over t entire surf e t produce an image of the heating element, the cathode visual light rays whi 111 illuminate a emanations are uniform in densityas to a cross- 45 stantial area around the device. Since a very section thol'ugh the beam, and, therefore, unilarge area is producing illuminating light formly activate the luminescent substances on the intensity of the illumination is not condensed the luminous e, e eby obviating bri t in a small spot as is the case with the ordinary sp ts or an ov a f y particular pa electric light. The result is less dense shadows of the anode luminous surface. 50 and less eye strain for the same total amount of Furthermore, by Obtaining h n cessary volillumination. Since the luminosity of the fluoume of cathode emanations from a large surface, rescent material emanates directly from the surthe required volume of emanations to obtain deface which is bombarded, much more brilliant sirable activation of the luminescent material is 5 luminescence is obtained than where luminous accomplished by the use of a relatively low volt- ;anode in various ways, one of cient for this purpose, and tuning of the regenerative circuit is accomplished by the reactance coils.

used bands of radio frequency. The majority of the wiring for operating the present device is. concealed or shielded so that there is little danger of from the device extending to any distance from the apparatus and thereby there is very little danger of any interference in the radio field even with ratus working on the same wave length.

Preferably, the luminescent materials utilized to produce the luminescent anode screen are suitable well known luminescent salts, for example, synthetic willemite, that may be supplied with a sufilciently small amount of oxygen that is so combined with the salt activate the luminescent material. cent materials may be applied to the metallic which is to apply a thin coating of sodium silicate to the anode and then spray powdered luminescent material in dry particles to the metal anode. I Preferably, the transformer coils and the cirport the tube; and preferably, the shielded parts Other features and objects of the present in a radio appapresent disclosure is to be understood as illustrative and not in the limiting sense.

Referring now more especially to the drawings forming a part of this specification:-

Fig. l is an elevational view of a complete device comprising the preferred embodiment of the present invention.

Fig. 2 is a more or less diagrammatic view illustrating the electrical circuits and showing portions of the device in section.

Fig. 3 is a detailed view of the cathode emitter and the electronic lens showing the parts in section.

Fig. 4 is Fig. 3.

Referring now to the drawings and more particularly to Fig. 1, a base I encloses transformer coils, etc., and is provided with ventilating openings 2 which are covered by shields preferably formed integral with the base. A conduit tube 5 leads from a view on the section line H of socket 52, which plate is grounded.

The various configurations of the figure comand other colors arranged as desired figure. These colors are not apparent until the device is in operation, at which time they stand out brilliantly.

Referringnow to Fig. 2, the operating current as 110 volt alternating current to the primary I 5 of a transformer. The

secondary it of the transformer may be tapped in such manner as to establish a relatively high voltage between the fluorescent anode 8 and the cathode emitter i7, This circuit I8-I9 preferably carries substantially 5000 volts. The secondary is also tapped to provide a low voltage circuit Iii-20 of preferably 10 volts to provide electrical energy for heating the heating coil 2! (Figs. 3 and 4) of the cathode emitter ll. An electronic lens 22 is supported in position to emor electronic lens is preferably constructed of metal in the frustum of a hollow cone.

is covered by luminescent salts. Preferably, the

6 in which are coated surface of this anode 8 presents an inclined area to the spread beam of electrons in such manner that the electrons are efiectively directed against the surface to activate the salts 21 thereon.

The circuit 18-44 is provided with a pair of reaction coils 28 and 29 which are inductively coupled and are suitably wound in such manner as to establish regeneration in the tube circuit. The internal resistance of the tube presents sufficient impedance to permit the reactance coils 28-29 to be so tuned as to establish the desired oscillations, and preferably, these oscillations are 3000 k. c. or a wave length of substantially 150 meters.

Referring now to Figs. 3 and 4, the cathode emitter l1 comprises a shell 30, preferably of nickel, which is closedby a flanged disc 3| to enclose a heating element 32 that is preferably in the form of a flat spiral. ,This heating element is connected at one end to the shell 30 and is connected at the other end with the circuit wire 20. The wire passes through an insulating tube 34, thereby insulating this portion of the circuit from the shell or flanged disc 3i. The circuit wire I9 is attached to the disc 3| or the shell 30, thereby completing the circuit through the heating element 32. Preferably, the flanged disc 32 is welded permanently to the shell 30. The heating element 32 is arranged adjacent the top of the shell 30 which carries a coating 35 of electronic emitting oxides or materials well known in the art. The effect of the heating element is to radiate heat directly to the top of the shell and to heat this portion of the sheet uniformly, thereby uniformly heating the emitter coating 35, consequently, obviating ,any pattem which would be produced by emitted electrons if the heating element were directly coated with the emitting material. Preferably, the cathode emitter is surrounded by a heat reflecting shell 36 which may have a polished interior surface to prevent escape of heat rays from the hot cathode. This erably is grounded by connection 31 with the circuit 19. 3

The secondary l6 of the transformer is also preferably grounded by the connection 38 to the transformer core 39.

Luminescent salts 21 may be placed closely adjacent to the anode 8 but preferably are mounted directly on the anode and they may be secured to the anode 8 by various means, but preferably, by the use of sodium silicate as a cement applied to the anode which is then covered by small particles of the said luminescent materials. This heat reflector prefmetallic anode may which may be utilized to provide a small amount of oxygen which seems to react with the luminescent salts to increase their life and brilliance.

During the manufacture of the tube, after the parts are assembled, the tube is exhausted to as high a degree of vacuum as is attainable by the present well known means of exhausting tubes of this character, so that the electronic bombardment of the luminescent salts on the anode within the tube is carried out in an extremely high vacuum. The results are that the tube runs with a very low expenditure of electrical energy for the amount of illumination obtained. In other words, the device comprises a very efficient apparatus for transforming electrical energy into light rays. The luminescent salts may be combined in different ways by utilizing salts well known in the art to produce any shade of color desired and also to produce white light which is a very close simulation of sunlight. The colors may be blends, or may be distinctive in the form of pictorial representations, or the salts may be used to produce solid colors as a source of colored light.

What I claim is:-

1. A cathode ray tube comprising a hot' cathode, an anode, disposed at an acute angle to the path of emitted particles from the cathode, fluorescent material carried by said anode, dispersing means to disperse the particles from the cathode to cause the said particle emission zone to cover said anode, and a highly evacuated chamber enclosing said cathode and said anode.

2. A cathode ray tube comprising ahot cathode, an anode, fluorescent material carried by said anode, the surface of said anode carrying said fluorescent material presenting an obtuse angle to the direction of flow of electrons, dispersing means to spread the zone of particles emitted from the cathode to cover the anode, and. a. non-gaseous highly evacuated chamber enclosing said cathode and said anode.

3. A cathode ray tube comprising a hot cathode emitter of large area, flat spiral heating means adjacent said emitter to uniformly heat the same to produce a wide beam of electrons from said emitter, means to receive the full beam from said emitter and to cause said electrons to spread into a conical shaped beam, an anode disposed at an acute angle to said beam and carrying luminescent material in the path of said beam and being adapted to be bombarded by said beam, and an envelope within which said beam is effective.

GILBERT T. SCHMIDLING.

be covered with an oxide 

